Answer:
x = 1.8
Step-by-step explanation:
We have the equation -3x + 18 = 7x. First we do your step 1, and get: 18 = 10x. When doing your step 2, we divide both sides by 10 to isolate x alone. 18/10 = 1.8. X = 1.8
The equation that passes through these points is x = 4
Answer:
2.5% probability that a randomly selected book has fewer than 133 pages.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 189 pages
Standard deviation = 28 pages
What is the probability that a randomly selected book has fewer than 133 pages?
133 = 189 - 2*28
So 133 is two standard deviations below the mean.
The Empirical Rule states that 95% of the measures are within 2 standard deviations of the mean. The other 5% is more than two standard deviations distant from the mean. The normal distribution is symmetric, which means that of those 5%, 2.5% are more than 2 standard deviations below the mean and 2.5% are more than 2 standard deviations above the mean.
This means that there is a 2.5% probability that a randomly selected book has fewer than 133 pages.
The other person did not explain so I will:
(68+79+74)= 221/3 =73.7
80 x 4 = 320
320-221 = 99
He must get 99 on his 4th test.
Thanks
